Sulphur condenser



G. H. GLEAsoN ET A1.

July 28,1936.

SULPHUR CONDESER Original Filed March 3l, 1932 NMAQQ@ l VTI.;

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S |NVx-:NToR5 Gwfge 6/ea5on YAY/'76d C. Loana/n ATTORNEYS Patented July28, 1936 UNET D STATS AlfredgC.. Loonam, Brooklyn,

N. Y., assignors to Guggenheim Brothers, New York, N. Y., a

copartnership Original application March 31, 1932, Serial No.

602,237. Divided and this application September 6, 1934, Serial No.742,912

l Claims.

. This invention relates to the recovery of sulphurgand has for .itsobject the provision of improved .apparatus for recovering elementalsulphur from sulphur-'bearing gases.

YThis application is a division of our application Serial No. 602,237,led March 31, 1932 (Patent No. 1,972,884).

It has long been known Athat sulphur can .be obtained fromV gasescontaining sulphur dioxide by treatment at an elevated temperature witha reducing agent, for example, in accordance with the followingreactions when carbon is employed vas the reducing agent:

However, no entirely satisfactory or successful commercial processutilizing these reactions has heretofore been developed, partly -becauseof the difficulty of recovering the sulphur in a form which can behandled easily and cheaply. Most of the processes heretofore proposedeither do not specifically state -how the sulphur is to be recovered orassume its -collection Vin a i'lnely divided form, a procedure which notonly presents all of the di'iculty and expense `of separat- 'ingfinelydivided solids-from gases but yields a product which is not easilyhandled. y

The most convenient form in which to recover sulphur is as a liquid.This has presented certain diculties, however, for the followingreasons:

(1) Sulphur vapor at temperatures below its normal boiling pointpolymerizes to Se and Ss, thereby greatly lowering its partial pressureeven in a .comparatively rich gas. A

(2) Liquid sulphur, inthe temperature range between 160 and 225 C., isextremely viscous, so much so, in fact, that at 190 C. a vessel contain-`ing it can be inverted without the sulphur running out. While it is uidabove this temperature range, its vapor pressure is comparatively high.and it is spontaneously inammable.

(3) The very low thermal conductivity of sul- .phur itself.

'The most favorable temperatures :for condensing sulphur are, therefore,in the lower fluid temperature range of 114 to 150 C. To secure Ycol-.lection of the condensed sulphur in this temperature range, the sulphurvapor (or gases containing sulphur vapor) must be cooled rapidly tobelow 150 C., and the resulting cooled vapor vor droplets of sulphurappropriately collected. The

,former condition may be obtained by providing suitable arrangements andconditions for efcient heat transfer 'and .the latter by bringing .thegases in contact with a powerful `solvent for sulphur.

In ,accordance with our present invention, the first condition isattained ,by providing means for bringing the gases into contactv withefficiently cooled surfaces of large area, thereby obtaining .rapidcooling .of thegasesbelow the Viscous temperature range fof liquidsulphur. The second condition .is.attained by providing means forbubbling the resulting sulphur-bearing gases through vliquid sulphurmaintained at a temperature in the lower iiuid range.

We have found that the practical attainment of these conditions isconveniently accomplished -by surrounding the condensing chamber with aliquid having a boiling pointwithin the lower -:fluid -sulphurtemperature range, thereby securing rapid dissipationaof heat onone'side of the chamber walls. Monochlorobenzene (the boiling point .ofwhich .is about '132 C.)., or water under a -pressure of .10 to 30pounds per square inch are appropriate liquids for the purpose.

We have .found it desirable to construct the sulphur condenser so thatthe gases bubble through liquid sulphur one or more times, there- :byinsuring intimate contact between gas and liquid and 4preventing theformation of ,an insulating .gas lm on the surface of the liquid. VThedepth of .liquid through which the gas passes .need not be very great,4'1/2 inches being ample, .and several passes through shallow layers areto bepreferred to one pass through a greater depth. Following thisprocedure, welhave found it practicable to Vcollect over 94% of thesulphur content -o'f -a gas mixture containing only 6.5% sulphur 5byvolume as (Se) Y When -the sulphur-bearing gases contain deleteriouscontaminants'which might'sep'arate out v with and -contaminate thesulphur product, we :prefer to Asubject the .gaseous .product to apre-:paratory ,cleansing treatment yby passing it in [contact -with :molten.sulphur at 1an elevated temperature. The apparatus of the inventioncomprises means .for Acarrying out such .a preparatory treatmentiifdesired. The condenser of the invention may kbe .employedalone or inconjunc- .tion with Vsuch cleansing means.

The accompanying drawing illustrates,some what x'liagrammatically,apparatus embodying `the principles 'of Vour invention. In `thisdrawing,

Fig. .-1 is a top plan view lof la condenser .embodying the invention,and

.-Fig. .2 is .a `sectional :elevation :on the section line 2 2 of Fig.il, :and showing 4`in addition, a

the inclined bottom I is lowered, and the gast` outlet I2 and the moltensulphur outlet I3 are through the end wall B, where the inclined bottomI0 is highest. The condensing' chamber issurrounded by a casing I4, ofsheet steel o r the like, suitably spaced therefrom to provide an'appropriate jacket for the heat dissipating medium.

Transverse and vertically disposed hollow par-1 titions or baffles I5depend from the top 9 of the condensing chamber to within a shortdistance of the inclined bottom I0.

I5 are` transverse and vertically disposed hollow ballles or partitionsI6 extending from the inclined-bottom I0 to within a short distance ofthe top 9. The hollow interiors of the baflles I5 and I6 communicatewith the jacket formed between the condenser walls andthe casing I4. Itis our preferred practice to extend one wall of the hollow partitions I5a short distance below the jacketed or hollow part of the partition toform a lower barrier I5.

Pipes I1, or other appropriate channels, provide communication formolten sulphur from one side to the other of the partitions l5. more ofthe partitions I5, near the discharge end of the condensing chamber, areprovided near their upper ends, on the gas-enteringy side,1withtransverse baffles I8 to knock down large globules of condensed sulphurentrainedwith the gases. The height of the discharge end of the moltensulphur outlet I3 is preierably'adjustable in order to appropriatelycontrol the level of the molten sulphur on the bottom of the condenser.`,An-inlet I9 is provided for the admission of the cooling or heatdissipating liquid medium to the jacketed portions of the condenser, andthe top of the casing I4 has an opening 20 for the escape of vapor. Thecondensing chamber proper 1s supported on the bottom of the casing I4 byI- beams 2|, or other appropriateform of support. In operation, thegases containing sulphur vapor enter the condenser through the pipe Iland flow downwardly into contact withA the molten sulphur on theinclined bottom IIJ. The gasesY then pass .under the first barrier I5and bubble through the layer of molten sulphur in the bottom of thenextvchamberB. Flowing upwardly through the chamber B and downwardlythrough the chamber C, the gases again bubble through molten sulphur atthe bottom of the kchamber D. And again the gases bubble through moltensulphur in passing from the chamber E to the chamber F.

The molten sulphur is maintained atits proper levels in the variouschambers by the gas pressure and by the positions of the barriers I5'and the height of the discharge end of the molten sulphur outlet-pipeI3.

The cooling or heat dissipating medium, having a boiling point between114 and 150 C. lls the jacketed portions of'the condenser. The Vapor ofthis medium, formed in the course of the con'- densation vof thesulphur, passes out through the outlet 20 Vand maybe eitherfcondensedand Between they baiiles One or Y returned or used for supplying heat orfor any other suitable purpose.

As a preparatory step to the condensation of the sulphur vapor, it isour preferred practice to pass the gaseous product containing thesulphur vapor in contact with molten sulphur at a temperaturebetween1450 C. and 250 C., as described in our copending applicationSerial No. 602,238, led March 31, 1932 (Patent No. 1,972,- 885)...vGaseous products containing sulphur vapor' may also contain materialswhich, if allowed to pass to the condenser, would separate out with andcontaminate the sulphur product. These contaminants vary with the sourceof the gaseous product and may be present in the solid, liquid or vaporstate. For example, the gaseous product from the reduction of sulphurdioxide by hot carbonaceous material may contain volatile `tarry mattersand solid particles of reducing agent'. The contemplated treatment ofthe gaseous product with molten sulphur, which is in the nature of awashing or scrubbing action, removes such contaminants. The treatmentmay be advantageously carried out in a tower 26 of suitable proportions,made of steel (suitably insulated) and iilled with a packing 22, such ascoke, Raschig rings, Chemico rings, or the like, to provide a large gascontact surface over rwhich liquid sulphur flows. The gas inlet 23 is atthe bottom and the gas outlet 24 at the top of the tower.` The sulphurused for washing may be introduced at the top of the tower as a spray orin ne streams, or the incoming gases may be brought in contact withliquid sulphur in a reservoirw25 at the bottom of the tower at atemperaturel highenough vto permit them to entrain an adequate amount of-sulphur vapor, which Vapor is allowed to condense and return to thereservoir by causing the temperature to decrease as the gases proceedupward toward the outlet. By the latter procedure, we cool the gases,obviate the necessity for a circulating pump, bring kcomparatively cleansulphur into contact withthe gases, and secure the benefits of the `factthat even fine particles or droplets in suspension act as condensationcenters and may be soladen with liquid sulphur that they settle out. Y j

Whileit is desirable that the exit gases be at such a .temperature thatthey contain the same amount o f sulphur as thek incominggases therebymaintaining a constant amount of sulphur in the washer, actualconditions of operations may make this impracticable. In such cases, theamount of liquid sulphur inthe washer will change and it will, benecessary to add or bleed oi sulphur from time to time.

Y The incoming gases may be bubbled through the liquid sulphur to-insure intimate contact. If ythe incoming gases do not contain enoughheat, it may be necessary to supply external heat principally at thebottom to secure circulation of sulphur. Part of the circulating sulphuris drawn off from time to time as the amount and nature of the collectedcontaminants may warrant and is replaced by clean sulphur. In -actualpractice, we have found that very satisfactory purification is obtainedwith an incoming temperature of the gases such that the temperature ofthe reservoir of liquid sulphur at the bottom of the washer is from 350C. to .450 C., and the washer is so designed and operated that the gasesexit at its topl at a temperature Vapproximately 100 C.

lower. Y

' zThe following example illustrates the eiciency of the washingoperation: VA collection of` sulphur fromthe gaseous product yof afurnace, inY which sulphur dioxide was reduced by coke, yielded aproduct which, although containing 98.8% S, was dark-colored and henceof inferior marketability. The inclusion of the washer in the sameinstallation resulted in raising the sulphur content of the product tobetter than 99.5%, and the color of the product was substantiallyidentical with that of present day commercial grades of sulphur orbrimstone.

From the top of the washer the Vgases are conducted to the sulphurco-ndenser.

It will be seen from the foregoing description that the condensation ofsulphur vapor (together with the collection of sulphur in the form ofmist or droplets) in accordance with the preferred form of our inventionis characterized by rapid cooling of the gas containing the sulphur to atemperature below about 150 C., and bringing the gas in contact withliquid sulphur at a temperature such that the sulphur particles coalesceto a collectible form of liquid sulphur of low viscosity.

The sulphur condenser of the invention is adapted for the condensationof sulphur vapor and for the collection of mechanically entrainedparticles of sulphur contained in a wide range of concentrations ingaseous products from Various operations, such, for example, as from thereduction of sulphur dioxide by hot carbonaceous material, eitherdirectly or incidentally in pyritic roasting or smelting operations inclosed top furnaces, from the distillation of pyrite or puricationresidues from gas works, etc. In actual practice, we have used thecondenser with distinct success in the complete process of recoveringelemental sulphur from gases containing sulphur dioxide, as described inour copending application, Serial No. 602,236, filed March 31, 1932(Patent No. 1,972,883).

We claim:

l. Apparatus for recovering elemental sulphur from sulphur-bearing gasescomprising a chamber of good heat conducting material provided with agas inlet and a gas outlet, one or more baffles disposed within thechamber between the inlet and outlet and so arranged as to provideduring normal operation of the condenser one or more bodies of moltensulphur through which the gas stream must pass, and a heat dissipatingliquid thermally associated with the walls of said chamber and with oneor more of the baffles and having a boiling point between about C. andC.

2. Apparatus for recovering elemental sulphur from sulphur-bearing gasescomprising a chamber having a gas inlet at one end and a gas outlet atthe opposite end, baiiles within the chamber for imparting a tortuouspath to the gas stream in its passage therethrough and for providingduring normal operation of the condenser one or more bodies of moltensulphur through which the gas stream must pass, and a heat dissipatingliquid thermally associated with the walls of said chamber and with saidbaiiles and having a boiling point between 115 and 150 C.

3. Apparatus for recovering elemental sulphur from sulphur-bearing gasescomprising a chamber having a gas inlet and a gas outlet, means withinsaid chamber for causing the gas stream in its passage therethrough tobubble through one or more bodies of molten sulphur, and a liquid heatdissipating medium thermally associated with said chamber and adapted torapidly cool .5.23 the gas stream entering the chamber through thetemperature range in which mol-ten sulphur is Viscous to a temperaturebetween 115 yand 150 C.

4. Apparatus for recovering elemental sulphur from sulphur-bearing gasescomprising a liquid sulphur reservoir having a gas inlet, a container ofgood heat insulating material packed'with inert material communicatingwith the liquid sulphur reservoir and provided with a lgas outlet,

a chamber of good heat conducting material:

provided with a gas outlet and with a gas inlet communicating with thegas outlet of the packed container, and one or more bailes disposedwithin the chamber between the inlet and outlet and so arranged as toprovide during normal operation of the condenser one or more bodies Yofmolten sulphur through which the gas stream must pass. "f v 5. Apparatusfor recovering elemental sulphur from sulphur-bearing gases comprisingafcon-ftainer of good heat insulating material having a compartmentforming a liquid sulphur reservoir and a communicating compartment'packed with inert material and provided with a gas inlet communicatingwith the liquid sulphur'reservoir and a gas outlet communicating withthe interior of the packed compartment, a chamber of good heatconducting material lprovided withfa gas outlet and with a gas inletcommunicating with the gas outlet of the packed compartment,

and one or more baiiies disposed within the chamber between the inletand outlet and so arranged as to provide during normal operation of thecondenser one or more bodies of molten sulphur through which the gasstream must pass.

6. Apparatus for reco-vering elemental sulphur from sulphur-bearinggases comprising a packed tower of good heat insulating material havinga liquid sulphur reservoir in its lower portion, a gas inletcommunicating with the interior of the liquid sulphur reservoir, a gasoutlet communicating with the interior of the upper portion of thetower, a chamber of good heat conducting material provided with a gasoutlet and with a gas inlet communicating with the gas outlet of thepacked tower, and one or more baiiles disposed within the chamberbetween the inlet and outlet and so arranged as to provide during normaloperation of the condenser one or more bodies of molten sulphur throughwhich the gas stream must pass.

7. Apparatus for recovering elemental sulphur from sulphur-bearing gasescomprising a packed tower of good heat insulating material having aliquid sulphur reservoir in its lower portion, a gas inlet communicatingwith the interior of the liquid sulphur reservoir, a gas outletcommunieating with the interior of the upper portion of the tower, achamber of good heat conducting material provided with a gas outlet andwith a gas inlet communicating with the gas outlet of the packed tower,one or more baffles disposed within the chamber between the inlet andoutlet and so arranged as to provide during normal operation of thecondenser one or more bodies of molten sulphur through which the gasstream must pass, and heat dissipating means associated with the wallsof said chamber.

8. Apparatus forI recovering elemental sul.. phur from sulphur-bearinggases comprising a packed tower of good heat insulating material havinga liquid sulphur reservoir in its lower portion, a gas inletcommunicating with the interior of the liquid sulphur reservoir, a gasoutlet communicating with the interior of the upper portion of thetower, a chamber of good heat conducting material provided with a gasoutlet and with a gas inlet communicating with the gas out- `fromsulphur-bearing gases comprising a packed tower of good heat insulatingmaterial having a liquid sulphur reservoir in its lower portion, a gasinlet communicating with the interior of the liquid sulphur reservoir, agas outlet communicating with the interior of the upper portion of thetower, a chamber of good heat conducting material provided with a gasoutlet and with a gas inlet communicating with the gas outlet of thepacked tower, a baiile extending between the side walls within thechamber between the gas inlet and the gas outlet and from the top wallto a point adjacent to but spaced from the bottom wall, a, sulphuroutlet communicating with the interior of the chamber on the side of thebaile opposite to the side on which the gas inlet is disposed and havingits discharge opening disposed from sulphur-bearing gases comprisingavpacked tower of good heat insulating `material having a liquid sulphurreservoir in its lower portion, a gas inlet communicating with theinterior Lof the liquid sulphur reservoir, a gas outlet communicatingwith the interior of the upper por-1 tion of the tower, a chamber ofgood heat conducting material provided with a gas outlet and with a gasinlet communicating with the gas outlet of the packed tower, two or morebaffles extending downwardly within the chamber between the gas inletand the gas outlet from the top wall to a point adjacent to butspaced-from the bottom wall and between the side walls, one or morebaffles extending upwardly between adjacent downwardly extending bafllesand between the side walls of the chamber from the bottom wall to pointsabove the lower ends of the downwardly extending baiiles, and a sulphuroutlet communicating with the interior of the chamber on the side of thebales opposite to the side on which the gas inlet is disposed and havingits discharge opening disposed above the lower ends of the downwardlyextending baflies.

GEORGE HOMER GLEASON. ALFRED C. LOONAM.

